# Test 3c: Demographic Trajectory Divergence Across Cohorts

*If early and late openers have diverging Z₁ paths, pooling creates mechanical attenuation.*

| Event Time | Early Z₁ Mean | (SD) | N | Late Z₁ Mean | (SD) | N | Difference |
|---:|---:|---:|---:|---:|---:|---:|---:|
| -10 | -- | (--) | 0 | -0.711 | (1.104) | 10 | -- |
| -9 | -- | (--) | 0 | -0.696 | (1.117) | 10 | -- |
| -8 | -- | (--) | 0 | -0.621 | (1.082) | 11 | -- |
| -7 | -- | (--) | 0 | -0.595 | (1.099) | 11 | -- |
| -6 | -- | (--) | 0 | -0.560 | (1.111) | 11 | -- |
| -5 | -- | (--) | 0 | -0.474 | (1.085) | 12 | -- |
| -4 | -0.543 | (1.575) | 3 | -0.457 | (1.082) | 12 | -0.085 |
| -3 | -0.522 | (1.571) | 3 | -0.414 | (1.038) | 13 | -0.108 |
| -2 | -0.444 | (1.298) | 4 | -0.382 | (1.031) | 13 | -0.062 |
| -1 | -0.429 | (1.309) | 4 | -0.357 | (1.027) | 13 | -0.072 |
| +0 **←open** | -0.316 | (1.147) | 5 | -0.330 | (1.038) | 13 | 0.014 |
| +1 | -0.285 | (1.141) | 5 | -0.312 | (1.048) | 13 | 0.027 |
| +2 | -0.274 | (1.143) | 5 | -0.293 | (1.051) | 13 | 0.019 |
| +3 | -0.255 | (1.159) | 5 | -0.273 | (1.058) | 13 | 0.018 |
| +4 | -0.217 | (1.153) | 5 | -0.252 | (1.075) | 13 | 0.035 |
| +5 | -0.195 | (1.145) | 5 | -0.227 | (1.088) | 13 | 0.032 |
| +6 | -0.182 | (1.143) | 5 | -0.208 | (1.096) | 13 | 0.026 |
| +7 | -0.174 | (1.144) | 5 | -0.185 | (1.112) | 13 | 0.012 |
| +8 | -0.140 | (1.145) | 5 | -0.170 | (1.123) | 13 | 0.030 |
| +9 | -0.099 | (1.135) | 5 | 0.012 | (1.001) | 12 | -0.111 |
| +10 | -0.064 | (1.122) | 5 | 0.032 | (1.011) | 12 | -0.096 |
| +11 | -0.029 | (1.113) | 5 | 0.045 | (1.019) | 12 | -0.074 |
| +12 | 0.002 | (1.107) | 5 | 0.060 | (1.034) | 12 | -0.058 |
| +13 | 0.038 | (1.115) | 5 | 0.093 | (1.087) | 11 | -0.055 |
| +14 | 0.080 | (1.110) | 5 | 0.102 | (1.086) | 11 | -0.022 |
| +15 | 0.104 | (1.120) | 5 | 0.121 | (1.155) | 10 | -0.017 |

**Average early-late Z₁ gap: pre = -0.082, post = -0.014**
*Gap stable or narrows → composition not the primary driver.*

*Transition economy openers only. Early: opening before 2000. Late: opening 2000 or after.*